Cardinality feedback

Quelques liens:
- http://dioncho.wordpress.com/2009/12/17/trivial-research-on-the-cardinality-feedback-on-11gr2/
- http://wedostreams.blogspot.com/2009/12/hidden-undocumented-and-adaptive-cursor.html 
- http://jonathanlewis.wordpress.com/2009/12/16/adaptive-optimisation/ 

En se connectant en tant que SYS, vous pouvez visualiser les caractéristiques d'un paramètre caché de la manière suivante:
select ksppinm as param,
       y.ksppstvl as ses_val,
       z.ksppstvl as inst_val,
       decode(bitand(ksppiflg/256,1),1,'TRUE','FALSE') as ses_modif,
       decode(bitand(ksppiflg/65536,3),1, 'IMMEDIATE',2,'DEFERRED', 3,'IMMEDIATE','FALSE') as system_modif,
       ksppdesc as descr
from x$ksppi x, x$ksppcv y, x$ksppsv z
where x.indx = y.indx
  and x.indx = z.indx
  and ksppinm like '\_%' escape '\'
order by ksppinm;